Clinical Study Of Pre-Injection Of Phenylephrine In Prevention Of Hypotension After Spinal Anesthesia In Elderly

Objective:To evaluate the efficacy and safety of prophylactic infusion of phenylephrine in the prevention and treatment of hypotension after spinal anesthesia in the elderly.Methods:Fifty-two patients undergoing artificial femoral head replacement from January2017 to April 2017 in our hospital and aged over 60 years were randomly and double-blindly divided into phenylephrine group and 0.9% isotonic sodium chloride solution group,26 patients in each group.Both groups received 0.5% bupivacaine 2ml for spinal anesthesia,phenylephrine group immediately received phenylephrine(100ug/ml)1ml/min after spinal anesthesia,and 0.9% isotonic sodium chloride solution group received 0.9% isotonic sodium chloride solution 1ml/min.observed the MAP and heart rate in the two groups of patients,as well as ECG abnormalities and troponin elevations within 48 hours after operation.Results:MAP in the phenylephrine group was higher than that in the 0.9% isotonic sodium chloride solution group(89.5 ± 1.7 vs 80.2 ± 1.6 mmHg,P<0.05).The number of hypotensive episodes per patient in the phenylephrine group was significantly less than that in the 0.9% isotonic sodium chloride solution group(2.96±2.85 vs 6.85±7.21 times,P<0.05).The number of hypotensive patients was similar between groups(18 [69%] vs19 [73%],P>0.05).The time to onset of the first hypotension in the phenylephrine group was significantly later than that in the 0.9% isotonic sodium chloride solution group(33.78±33.09 vs 5.47±3.96 minutes,P<0.05).The total dosage of phenylephrine in phenylephrine group was significantly higher than that in the 0.9% isotonic sodium chloride solution group(P<0.05).There was no significant difference in the total usage of liquid between the two groups(P>0.05).There was no significant difference in the number of patients with hypertension and bradycardia(P>0.05).There was no significant difference in the number of episodes of hypertension and bradycardia per patient between the two groups(P>0.05).There was no significant difference in the number of patientswith abnormal ECG changes between the two groups(P>0.05).There was no significant difference in the number of patients with elevated troponin between the two groups(P>0.05).Conclusion:Prophylactic infusion of phenylephrine can effectively prevent hypotension after spinal anesthesia in the elderly,reduce the number of episodes of hypotension,delay the onset time of hypotension,and improve the safety of surgical anesthesia.It is worthy of clinical application.